Large, industrial electric machines operate at extremely high energy levels. Industrial turbine generators, for example, may operate at voltages as high as 30,000 volts and currents as high as 15,000 amps. As a result, industrial electric machines utilize large, specially-configured conductors known as high-voltage conductors.
Two examples of high-voltage conductors that are commonly implemented in turbine generators are stator windings and parallel rings. Stator windings are located in the stator core of a generator. Stator windings conduct the alternating current and voltage induced by a generator's field windings. Parallel rings are located near the ends of a generator. Parallel rings provide an electrical path from the stator windings of a generator to the main leads. Parallel rings conduct the same high-level alternating currents and voltages that are conducted by stator windings.
High-voltage conductors, like stator windings and parallel rings, are mechanically supported within an electric machine by specially-configured support structures. The support structures often include rectangular spacer blocks for mechanically separating adjacent high-voltage conductors. These rectangular spacer blocks are generally positioned periodically between adjacent high-voltage conductors in order to maintain a fixed distance between them. This improves the mechanical performance of an electric machine by providing rigid support for and separation of high-voltage conductors. However, conventional-rectangular spacer blocks also impair the electrical performance of an electric machine by increasing the chance of creep between the high-voltage conductors.
When high-voltage conductors are separated by a conventional-rectangular spacer block, they become susceptible to electrical flashover in the form of creep. To address this problem, high-voltage conductors can be further insulated or spaced farther apart. But, adding additional insulation to high-voltage conductor reduces their ability to dissipate heat. Moreover, spacing the conductors further apart causes an undesirable increase in the size of the electric machine.